This continuation builds on a research platform continuously funded since 1980 that has focused on the importance of targeting GSH and GST homeostasis in anticancer drug discovery and development. Aim 1 will address how human pharmacogenetics might influence the multiple functional properties of GSTP, particularly with respect to protein:protein interactions and the catalysis of S-glutathionylation. Aim 2 seeks to define mechanism(s) of action for a series of nitric oxide (NO) releasing, GSTP activated diazeniumdiolate prodrugs. Structure activity analyses will determine which metabolites of these drugs may act as proximal donors in the S-glutathionylation reaction. In Aim 3 we will elaborate on preliminary observations that serpina1 and serpina3 are S- glutathionylated in the plasma of drug treated animals and may represent novel biomarkers for drug pharmacodynamics or exposure to reactive oxygen or nitrogen species. Aim 4 extends Aim 3 into the bone marrow compartment where NOV-002 and Telintra (small molecule myeloproliferative drugs) may impart proliferative effects through S-glutathionylation of the protease inhibitor serpins. Mechanistically, these protein families are subject to redox regulation and have roles in regulation of marrow progenitor cell proliferation and mobilization into the bloodstream. Since some of the drugs under study are in clinical trial, there is a strong translational component to this work. Moreover, drug development is facilitated by goals to develop GST activated prodrugs and define their mechanism(s) of action.